A theoretical treatment has been given a model of the excitable membrane. This is based on classical physio-chemical forces. Good agreement with experiment has been achieved. The model is being refined, with especial reference to interface phenomena (adsorption of Ca ions, and dehydration energies). Experiments will now be conducted on both living and artificial membranes, to provide a check on theory, and possibly a better estimate of physio-chemical parameters used in the theory.